#include <bits/stdc++.h>

using namespace std;

ifstream fin ("transport.in");
ofstream fout ("transport.out");

vector <int> v;

bool isSolution (int sol, int k, int n)
{
    int lastVal = 0;
    for (int i = 0; i < n; i ++) {
        if (k == 0) return false;
        if (v[i] - lastVal > sol) {
            k --, lastVal = v[i - 1], i --;
        }
    }
    return true;
}

int main()
{
    int n, k;
    fin >> n >> k;
    int maxim = 0;
    int x;
    fin >> x;
    v.push_back(x);
    if (x > maxim) maxim = x;
    for (int i = 1; i < n; i ++) {
        int x;
        fin >> x;
        v.push_back(x);
        v[i] += v[i - 1];
        if (x > maxim) maxim = x;
    }
    int dr = v[n - 1], st = maxim;
    int sol = 0;
    while (dr >= st) {
        int m = (dr + st) / 2;
        if (isSolution(m, k, n) && m >= maxim && m <= v[n - 1]) sol = m, dr = m - 1;
        else st = m + 1;
    }
    fout << sol;
    return 0;
}